Locomotive fire box



@ci. 8, 1935. L. RICHARDSON LOQOMOTIVE FIRE BOX Fi'led June 2, 1934.Patented Oct. 8, 1935 UNITED STATES A'E'ENT OFFICE '7 Claims.

This invention relates to improvements in locomotive fireboxes and itconsists of the matters hereinafter described and more particularlypointed out in the appended claims.

" In the conventional type of firebox having inner side sheets,difficulties are encountered in preventing the cracking, breakingthrough and burning out of said sheets, particularly the lower halfadjacent the mud ring. These difficulties 'result because of. the morequiescent state of the water in the bottom of the side water legs of theboiler and also because of the extremely high temperatures which obtainin that part of the firebox especially where the fireboxis equipped l5with the usual refractory arch.

The changes in temperature to which the side sheets of'the firebox aresubjected when in use, cause'an expansion and contraction of the samewhich leads to their premature breakdown. Such 20 breakdowns oftenrequire sheet renewal which is not only costly to make but results inkeeping the locomotive out of service for some time, which it is desiredto avoid as much as possible.

Many expedients have been tried in an attempt 5 to overcome thedifficulties mentioned, with little, if any, success, due either to theinoperativeness of the said expedients or to the excessive costsinvolved and which made them impractical.

I am aware that corrugating the side sheets 30 of the firebox, eitherhorizontally or perpendicularly, has been attempted. While such aformation permitted the sheet to breathe somewhat, i. e. to come and gounder temperature changes, the cost was excessive andthe making ofrepairs andin patching the same or the renewal of the bottom end of saidsheets is an extremely difiicult, if not impossible, matter. I havefound that even with such corrugated side sheets, the breathingfmovementis not sufficient to loosen 40? scale or mud which adheres to the watersideof. the sheets with the result that such sheets soon burned out.

One of the objects .ofthe present inventionis to provide a firebox, thebottom portions of the 4 1 1111161 side sheets of which are so formedthat they will not readily burn-out or break through, during periods ofuse much longerthan is now possible with side sheets of any previousdesign.

Another object of the invention is to provide a firebox having sidesheets, formed with areas capable of a greater come and go or breathingmovement in the expansion and contraction of the sheets, so that thedeposits are loosened on the water side of the sheets, thus insuring aconstant Water engagement or contact therewith which 14 and. coact toprovide a front throat IS, a

prevents adherence of deposits to the side sheets and thus avoidingpremature destruction of the side sheet.

A further object of the invention is to provide a firebox, the bottomend of the side sheets of 5' which have longitudinally spaced,substantially vertically disposed, bulge portions therein, which act asflexible diaphragms to loosen deposits on the water side thereof so asto keep them clean and which diaphragms will permit sufiicient 10movement under expansion and contraction as to prevent cracking orbreaking through thereof. or the pulling away from the associatedstaybolts.

Still a further object of the invention is to provide a side sheet.structure for a firebox which 15 is not only capable of long'periods ofuse but which is economical to make in accordance with present shoppractices. I

The above mentioned objects of theinvention, as well as others,together; with the many advantages thereof, will more fully appear as Iproceed with my specification.

In the drawing:.

Fig. l is a longitudinal vertical section through a locomotive fireboxembodying the preferred form of the improved side sheets;

Fig. 2 is a horizontal detail sectional view through a part of thefirebox on an enlarged scale as taken on the line 22 of Fig. 1; and

ing drawing, and'especially to Fig. 1 thereof, the 5 fire-boxthereinshown includes the side sheets 44, (only one of which appears) theinside back sheet 5 and the front or flue sheet 6. The various sheetsmentioned are connected together at the top ,by the crown sheet 7 in theusual man- 40 ner. The bottom end of the fiue sheet is formed to providean inside front throat sheet 8. The outside back sheet is represented at9 and said sheet. and the inside back sheet are suitably connected bythe staybolts m. Both of these sheets are formed to coact in providingafuel door opening H. The outer side sheet is indicated at E3 in Figs. 2and 3. All of the sheets are connected at the bottom end by a mud ringback water leg 16 and side water legs [1, only one of which appearsinthe drawing. The throat and water legs mentioned all communicate withthe water space of the boiler in the conventional manner. 5

proper;-

to support the body portion of each diaphragm.

firebox, rearwardly to pass over the arch on theirway to the fluessecured in the flue sheet 6.

Because of the arch, the temperature in-=the lower part of the fireboxis extremely high-.and,.,.

there is some variation in temperature throughout the length of thefirebox due ltothemovements of the products of combustion aroundthe.end,

of the arch and due to the fact that the products arein various: stagesof-combustion.z The'water'a movement in the, :bottom; of the side waterlegs is not very vigorous so that the solids in. the watertendtmaccumulate-in the bottom: of said water legs'zandihereadhere tothe Water side .of the innerside sheets. This materially reduces thecooling .action'of the water on the inner side sheets anclbecause oftheextremely high temperature inJthat 'part of the-firebox, they burnout and. require-repair prematurely, relative to other parts ;of theside sheets.

To overcome such action, the inner side sheets are provided at:longitudinally spaced points therealong :with vertically elongateddiaphragms 22.0n the :fire: side :of thesheet. They are preferably of aheight. approximating that height of the sheet mostzseriously' afiectedby the action above mentioned.

As 'here showm each" diaphragm begins adjacent the plane of themudringand extends upwardly a suitable distance and has curved or roundedtop: and bott'om 'ends'.. Each diaphragmalso includes a central bodyportion'23 that is arranged in a plane inwardly of. theside sheetstaybolts 20 of increased length serve The body portionof each-diaphragmmerges at itssides and at its ends into the: adjacent portions of theassociated'inner side sheet by side and end marginal'porti'ons 24'and'25of substantially :ogee or reversely curved formation.

It is preferable that the width of the diaphragm be -lessthan thedistance between alternate vertical rows of staybolts, so that itscurved marginal portions merge into the fiat part of adjacent portionsof the side sheet. It is also pointed out that the central-bodyportionof each vertically elongated diaphragm is substantially flat forthe proper securement of the associated staybolts '28 therein. Y

The curves of the ogee side;and-top margins. of each diaphragm are madeon substantial-radii,

while the curves of the ogee bottom .marginof the diaphragmarepreferably .made ongreater radii as indicated atr25ain Fig. 3. Thisdecreases. the pocket effect at the.;bott0m end of the dia.

phragm. onthe water side thereof. and hence,

avoids .the collection of solids therein .to any. appreciable extent...Furthermore, .thislendpf the diaphragm being adjacent the. mud. ring andbeing-influenced. by the attachment of this portion of the.sheet..thereto,.provides. an increased flexibility that .offsetsthestiffness-pr resistance induced by its position relative to the mudring-,-

It will be observed that the central body portion of the diaphragm isspaced a greater distance from the outer side sheet than those portionsof the inner side sheets between said diaphragms. This increases thewater space in back 5 of each diaphragm so that the water column at thatpoint is of greater depth and is therefore, capable of absorbing heatmore effectively and to a greater degree. Thus a turbulence is createdinthewaterspacein line-.with' or lbackeof each 10 diaphragm whichassists water circulation, and discourages or prevents to a considerableextent, the.-.accumulation of water solids, on the water side of thediaphragms.

Thediaphragms also permit and develop a 15 greaterzcome and. go orbreathing movement of the sidesheet portions involved, which greatermovement breakspup tand dislodges any accumulationof .water solids onthe water side thereof. Thusthe diaphragms-remain relatively cleaner 20and will notsso 4 quickl-ygbur-n, out.

Again, it is pointed .out that with the. rounded ends-described, thediaphragm can move inwardly and outwardly .as-a unit as itdoes-notmerge;

at itssends into the adjacent portionof theaside 25;,

sheets with such labruptness-ras to rprevent' the movement intended.

Should it ever become necessary to renewthe lower half of the-sidesheetor to make-patches in thisportion of the side sheets,.or should one-30of thediaphragms requirerenewal, this-would. be;-. an easy matter-as nocomplicated matching of sheet and surface parts isrequiredc The-boilerillustrated-is that of a large modern. locomotive in which-the fireboxhasalength of 35 the order ofone hundredfifty inches. In=a locomotive ofthis sizeI find that threediaphragm portions are very satisfactory Ifthefirebox. were much longer or much shorter ,a greateror lesser 'numbenofdiaphragm..-.portions might .be

required. The number .of diaphragm. portions should be suchmthat theflexure of...the water surface of thelside sheetsshall be withingtheelasticv-limit .of 1 the metal. but shall exceed ,the

elastic limit of the scale or the adhesionofthe scale .to the "metal.

While-in. describing the invention, I have referred in detail .to. the.form, arrangement andconstruction ofthe par tsrinvolved, the v.same isto be considered only in an: illustrative sense so that -I donot wish;to be. limitedtheretoexcept as may be specifically set forthintheappended claims.

I claim. as my .invention:

1. A firebox embodying-therein inner and outer side sheets, asubstantially vertically arranged, elongated-inwardly bulged diaphragmportion. in said innerside -sheet..having parallel sides and.roundedends that .merge intothe saidsheet .by

margins ofv reverse .curve crosssection, and stay:

bolts connectingsaidsheets, certain-ofsaid staybolts connecting saidbulged diaphragmportion to said outer. side.sheet.-

2. A firebox embodying-therein inner and outer.

sidesheets, a substantially vertically arranged,

Ofboth sheets are connected, the inner side sheet having a plurality oi!longitudinally spaced, substantially vertically arranged, elongateddiaphragm portions with substantially rounded ends, the rounded bottomend of each diaphragm portion being arranged adjacent the plane of thetop of the mud ring, and staybolts connecting said sheets, certain ofsaid staybolts connecting each diaphragm portion to said outer sidesheet.

4. A firebox embodying therein inner and outer side sheets, a mud ringto which the bottom ends side sheets, a mud ring to which the bottomends 7 of both sheets are connected, a fire arch in the firebox betweensaid inner side sheets, a plurality of longitudinally spacedsubstantially vertically arranged, elongated diaphragm portions in saidinner side sheets having substantially rounded ends, the bottom end ofeach diaphragm portion being arranged adjacent the plane of the top ofthe mud ring and thetop end of certain of said diaphragm portionsterminating in staybolts connecting said side sheets, and asubstantially vertically arranged, elongated, inwardly bulged diaphragmportion arranged in said inner side sheet between certain of the boltsin alternate rows with certain of the bolts in the intermediate rowarranged to connect themedian line of said diaphragm portion with saidouter side sheet, the said diaphragm portion having substantiallyparallel sides and having substantially rounded ends.

7. A firebox embodying therein inner and outer side sheets, the innerside sheet having a substantially vertically arranged, elongateddiaphragm portion'with substantially parallel side marginsand roundedtop and bottom end margins, the side margins being connected to the bodyof the inner side sheet by reverse curves of one radius and the bottomend margin being connected to the body by reverse curves of a differentradius, and staybolts connecting said sheets with certain of saidstaybolts arranged to connect said diaphragm portion to said outer sidesheets a V LAWRENCE RICHARDSON.

